Yeast fermentation solution

1、 Introduction

Yeast fermentation, as an important biotechnology method, is widely used in fields such as food, medicine, chemical engineering, and bioenergy. This plan aims to develop a comprehensive and efficient yeast fermentation process, including the selection and cultivation of strains, preparation of fermentation substrates, setting of fermentation environment, control of inoculation amount and time, monitoring of the fermentation process, collection and purification of products, evaluation of fermentation efficiency, and subsequent processing and preservation, to ensure the smooth progress of the fermentation process and the high quality and high yield of the final product.

2、 Selection and cultivation of bacterial strains

1. Strain selection: Select the appropriate yeast species based on the fermentation target (such as alcohol production, bread fermentation, biopharmaceutical precursor synthesis, etc.), such as Saccharomyces cerevisiae, Pichia pastoris, etc. Consider the growth rate, tolerance, product specificity, and safety of the bacterial strain.

2. Culture of bacterial strains: Activation and amplification of bacterial strains are carried out using methods such as inclined surface culture and liquid shake flask culture. Ensure that the components of the culture medium are suitable for the growth of the target strain, such as glucose, nitrogen sources (yeast powder, peptone), inorganic salts, and trace elements. Control the cultivation temperature, pH value, and ventilation conditions, regularly observe the growth of bacterial cells, and timely subculture to maintain bacterial vitality.

3、 Preparation of fermentation substrates

1. Substrate selection: Select suitable substrates according to the fermentation process requirements, such as sugars (glucose, sucrose), starches (corn starch, potato starch), etc. Consider the cost, availability, and impact of substrates on the fermentation process.

2. Pre treatment: Necessary pre-treatment of the substrate, such as crushing, liquefaction, saccharification, etc., to improve its fermentability. Ensure that there is no harmful microbial contamination in the substrate and adjust it to the appropriate pH and temperature.

4、 Fermentation environment setting

1. Temperature control: Set the appropriate fermentation temperature based on the characteristics of the bacterial strain. Generally, the fermentation temperature of brewing yeast is between 30-35 ℃.

2. pH adjustment: By adding acid-base regulators to maintain the pH value of the fermentation broth within an appropriate range, the pH value of yeast fermentation is usually between 4.0-6.0.

3. DO regulation: Through system linkage control, the dissolved oxygen value of the system is automatically controlled by the speed and ventilation volume. The pH value of yeast fermentation is usually between 40-60%

4. Ventilation management: Adjust the ventilation rate according to the fermentation type (aerobic fermentation or anaerobic fermentation) to ensure sufficient oxygen supply or create an anaerobic environment.

5. Nutrient supplement: According to the fermentation process, the system automatically supplements carbon sources, nitrogen sources, nutrient solutions, inducers, etc.

5、 Vaccination amount and time

1. Inoculation amount: Determine a reasonable inoculation amount based on the growth of the strain and the capacity of the fermentation equipment, generally ranging from 1% to 10% of the volume of the fermentation broth.

2. Inoculation time: Inoculate immediately after substrate pretreatment is completed and the fermentation environment is stable to shorten the lag period and improve fermentation efficiency.

6、 Fermentation process monitoring

1. Biomass monitoring: Regularly measure the concentration of bacterial cells in the fermentation broth to understand their growth status.

2. Product concentration monitoring: Use methods such as spectrophotometry and chromatography to monitor changes in the concentration of the target product.

3. Monitoring of metabolic byproducts: Monitor potential harmful byproducts such as organic acids, ethanol, etc., and adjust fermentation conditions in a timely manner.

7、 Product collection and purification

1. Collection: Select appropriate collection methods based on the characteristics of fermentation products, such as centrifugation, filtration, distillation, etc.

2. Purification: Further purify the product through chromatography, crystallization, ion exchange, and other methods to improve purity.

8、 Fermentation efficiency evaluation

1. Yield evaluation: Compare the actual yield with the theoretical yield and calculate the fermentation yield.

2. Cost control: Analyze raw material costs, energy consumption, labor costs, etc., and evaluate the economic viability of the fermentation process.

3. Environmental impact: Evaluate the potential impact of the fermentation process on the environment and propose improvement measures.

9、 Subsequent processing and storage

1. Fermentation waste disposal: Dispose of the waste generated during the fermentation process, such as wastewater, waste residue, etc., in accordance with environmental protection requirements.

2. Strain preservation: The selected high-quality strains will be stored in glycerol tubes, liquid nitrogen ultra-low temperature storage, and other methods for future use.

3. Fermentation equipment maintenance: Regularly clean and disinfect the fermentation equipment to maintain its good operating condition.

By implementing the above plan, the scientific and efficient fermentation process of yeast can be ensured, providing strong support for product production in related fields.